DERIVATIVE FINANCIAL INSTRUMENTS - Additional Information (Details) - USD ($) $ in Thousands	Jun. 30, 2026	Dec. 31, 2025
Derivative [Line Items]
Percentage of periodic changes in fair value qualifies for hedge accounting treatment	100.00%
Hedge gain to be reclassified to interest income during next twelve months, net	$ 1,700
Hedge gain to be reclassified to interest expense during next twelve months, net	11,700
Interest rate swaps on borrowings \| Cash flow hedges: \| Designated as Hedging Instrument
Derivative [Line Items]
Notional amount	50,000	$ 50,000
Interest rate swaps on borrowings \| Fair value hedges: \| Designated as Hedging Instrument
Derivative [Line Items]
Notional amount	800,000	1,100,000
Interest rate swaps, collars, and floors on loan pools \| Cash flow hedges: \| Designated as Hedging Instrument
Derivative [Line Items]
Notional amount	3,200,000	2,300,000
Interest rate swaps on investment securities \| Fair value hedges: \| Designated as Hedging Instrument
Derivative [Line Items]
Notional amount	874,407	927,407
Interest rate lock commitments \| Not Designated as Hedging Instrument
Derivative [Line Items]
Notional amount	117,675	81,698
Forward mortgage loan contracts \| Not Designated as Hedging Instrument
Derivative [Line Items]
Notional amount	134,702	120,584
Customer and offsetting counterparty derivative instruments \| Not Designated as Hedging Instrument
Derivative [Line Items]
Notional amount	$ 10,600,000	$ 9,900,000

Interest Rate Cash Flow Hedge Gain (Loss) to be Reclassified To Interest Expense During Next 12 Months, Net

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- Definition

Interest Rate Cash Flow Hedge Gain (Loss) to be Reclassified To Interest Income During Next 12 Months, Net

+ References

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- Definition

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 815
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 5A
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480434/815-10-50-5A

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 505
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 18
-Subparagraph (c)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481112/505-10-50-18

Reference 3: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 815
-SubTopic 20
-Name Accounting Standards Codification
-Section 25
-Paragraph 6A
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480682/815-20-25-6A

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Nominal or face amount used to calculate payment on derivative.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 815
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 1A
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480434/815-10-50-1A

Reference 2: http://www.xbrl.org/2003/role/exampleRef
-Topic 815
-SubTopic 10
-Name Accounting Standards Codification
-Section 55
-Paragraph 181
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480401/815-10-55-181

Reference 3: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 815
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-Name Accounting Standards Codification
-Section 50
-Paragraph 1B
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480434/815-10-50-1B

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